Catheters are used for many medical procedures, including inserting a guide wire, delivering a stent, and delivering and inflating a balloon.
Catheterization procedures are very commonly performed for diagnosis and treatment of diseases of the heart and vascular system. The catheterization procedure is generally initiated by inserting a guide wire into a blood vessel in the patient's body. The guide wire is then guided to the desired location, most commonly in one of the heart vessels or elsewhere in the vascular system. At this point the catheter is slid over the guide wire into the blood vessel and/or heart. Once the catheter is in the desired position, the guide wire can then be removed, leaving the catheter in location. Alternatively, in some procedures, the catheter is inserted without using a guide wire. The catheter may be used to pass ancillary devices into the body, such as an angioplasty balloon, or to perform other diagnostic or therapeutic procedures.
Thus, at the present time the guidance of catheters and other medical devices in body lumens and cavities is still most often accomplished by providing a bent tip on the device or using a guide wire with a bent tip.
To insert a catheter manually, the physician applies torque and axial push force on the proximal end of a guide wire to effect tip direction and axial advancement at the distal end. However, it is difficult to control the distal tip of the catheter from the proximal end. Although these navigation techniques are effective, they are tedious, require extraordinary skill, and result in long medical procedures that fatigue the user.
Furthermore, to facilitate the guide wire insertion and the subsequent catheter application, the physician generally performs the procedure with the assistance of a fluoroscope, as is well known in the art. The fluoroscope produces a real-time image showing the continued progress of the guide wire, or the catheter, through the patient's body.
The fluoroscope generates a high level of X-ray radiation, which poses a significant danger to medical personnel exposed thereto, as is well known in the art. In order to provide protection from radiation exposure, the attending medical personnel generally wear a heavy, cumbersome protective lead garment which covers the entire body and neck, or use various lead shields including transparent glass face and eye shields. The use of fluoroscopy in the catheterization lab presents safety concerns for training, monitoring, and record keeping among the catheterization lab staff. The staff constantly monitors the radiation dosage that each member receives.
One solution for these problems is proposed by U.S. Pat. No. 6,522,909 (2003) Garibaldi, et al, “METHOD AND APPARATUS FOR MAGNETICALLY CONTROLLING CATHETERS IN BODY LUMENS AND CAVITIES”, which provides an apparatus for navigating a magnet-tipped medical device through the body including a magnet system for applying a magnetic field to the magnet-tipped distal end of the medical device to orient the distal end of the medical device; a computer for controlling the magnet system to generate a specified magnetic field in the body part; first and second imaging devices connected to the computer, for providing bi-planar images of the body part through which the medical device is being navigated; first and second displays for displaying the images from the image devices; and an input device for inputting points identifying the desired path of the medical device on each of the displays. The computer is programmed to determine the magnetic field necessary to control orient the medical device on the path input on the displays.
However, U.S. Pat. No. 6,522,909 requires expensive and bulky equipment.
U.S. Pat. No. 5,779,623, POSITIONER FOR MEDICAL INSTRUMENTS (1998) Bonnell, features a remote-controlled device for selectively positioning a medical instrument within a predetermined region of space. The remote-controlled device has a motor which provides mechanical energy to the remote-controlled device, a driver that is coupled to the motor and that has a predetermined relationship with the motor. The driver physically engages the medical instrument and converts the mechanical energy into controlled motion of the medical instrument. The remote-controlled device receives control signals from a remote location that direct the motor to supply a predetermined amount of mechanical energy, whereby the driver, with the predetermined relationship with the motor, selectively positions the medical instrument within the region of space.
However, U.S. Pat. No. 5,779,623 does not provide rotational movement of the medical instrument, nor position feedback, nor a fast method for inserting and removing the instrument.
U.S. Pat. No. 6,726,675 REMOTE CONTROL CATHETERIZATION (2004), Dalia Beyar, describes a remote control catheterization system including a propelling device, which controllably inserts a flexible, elongate probe into the body of a patient. A control unit, in communication with the propelling device, includes user controls which are operated by a user of the system remote from the patient to control insertion of the probe into the body by the propelling device.
It is an object of some aspects of U.S. Pat. No. 6,726,675 to provide an apparatus and methods of catheterization that allow medical personnel to be distanced from the vicinity of the fluoroscope and its resultant radiation, thereby reducing radiation exposure of the personnel. It is a further object of some aspects of the U.S. Pat. No. 6,726,675 invention to provide a mechanism for remote control performance of catheterization procedures.
The present invention is intended to provide a transmission mechanism for a remote catheterization system, such as that provided in U.S. Pat. No. 6,726,675.
In a preferred embodiment of the present invention, the transmission is a mechanical assembly that holds a slender and greatly elongated solid medical component, such as a catheterization guide wire, between two pressure rollers. Linear motion of the guide wire is accomplished by motorized rotation of the rollers on their axes. Rotational motion of the guide wire is accomplished by motorized rotation of the assembly, which holds the rollers and the guide wire, around the guide wire's linear axis. Movement combining advance and rotation can be accomplished as well.
In summary, it is a main object of the present invention to provide a mechanical transmission for movement of a guide wire in a remote control catheterization system, with the following several objects and advantages:                Translates motor force into linear and rotational motion of the guide wire or other slender and greatly elongated solid medical component.        Can perform both linear and rotational motion simultaneously        is simple and mechanically reliable        provides two ways to mount guide wire in transmission: end insertion and side insertion        
In end insertion, the guide wire is fed into the transmission along the guide wire's longitudinal axis until the desired point on the guide wire is reached. In side insertion, a slot in the transmission enables the guide wire to be inserted directly at the desired point, with no need for feeding. The same principles apply when removing the guide wire from the transmission.
Still further objects and advantages will become apparent from a consideration of the ensuing description and drawings.